hobbs



(No Model.) A J. T. HOBBS.

SAFETY MECHANISM FOR. OPERATING ELEVATOR GATES.

No. 571,442. Patented Nov. 17, 1896.

TaanE- ATTEET Iw/ Ema-EF TFTKR LM v u MPMLV' BY ATTs' UNITED STATESPATENT OFFICE.

JOHN T. HOBBS, OF CLEVELAND, OHIO, ASSIGNOR TO THE CLEVELAND SAFETY GATECOMPANY, OF SAME PLACE.

SAFETY MECHANISM FOR OPERATING ELEVATOR-GATES SPECIFICATION forming partof Letters latent No. 571,442, dated November 17, 1896.

- Application filed April 3, 1896. $e1ial No. 586,064. (No model.)

To aZZ whom it 11mg concern:

- Be it known that I, JOHN T. HOBBS, a citi- Zen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented certain new and useful Improvements in Safety Mechanism for Opcrating Elevator-Gates; and I do hereby declare that the following is afull, clear, and exact description of the invention, which will enableothers skilled in the art to which it appertains to make and use thesame.

My invention relates to safety mechanism for operating elevator-gates,whereby the gate is automatically raised at the pleasure of the operatoras the car or platform approaches a landing either from below or above,and the gate is closed as the car or platform leaves the landing, allsubstantially as shown and described, and particularly pointed out inthe claim.

In the accompanying drawings, Figure l is an elevation, partly inperspective, of a portion of an elevator crib, platform, and gate and myimproved automatic mechanism in working position therewith. Fig. 2 is aseparate or detail view, enlarged, of the lower sprocket-wheel and thesame size of pulley as shown in Fig. 1. Fig. 3 is a detailof severaldifferent sizes of pulleys, all of which are adapted to be used ashereinafter fully described.

A represents a platform of a freight-elevator, but in lieu of this theremight be an elevator-car and the connections be made therewith instead.The usual uprights or guideways B for the platform or car are shown asbuilt into the well, and this or any other common construction can beused, the character or kind of elevator being immaterial, as my improvedattachments are intended to be applied to any of the usualpower-elevators found in warehouses, factories, shops, and other places.

C represents the gate, adapted to slide up and down in the front frameas usual, and the idea of the invention is to automatically raise thisgate from the platform A on the approach of the platform from eitherdirection if a stop is to be made, and at the option of the elevator-manas he goes from floor to floor. Thus the gate C is connected by rope 5,and is supported on the sprocket-wheel E by means of threaded bolts ortheir equivalent, so as to leave the pulleyfree to be disengagedwhenoccasion requires.

Immediately over and some distance above sprocket-wheel E is thesprocket-wheel G,

supported on fixed brackets or supports 7. The sprocket-chain 6 isstretched. over the sprocket-wheels E and G and carries lateralprojections 8 and 9. The said wheels are located a given distance apart,say, six feet, and are, say, eight inches across, so that threerotations carry the chain six feet. The projections 8 and 9 on the chain6 are therefore arranged to travel about six feet, which determines therise or lift of the gate. Now to see how this operates refer forillustration to Fig. 1, where the platform A may be considered to becoming down. This platform carries at its side the pawl 12 in verticalline with the lateral projection 9 on chain 6. Hence if pawl 12 is notthrown out by the operator it will engage projection 9 as it descends,carry chain 6 along, and thereby rotate pulley E and through cable Draise the gate C. The downward movement of the parts 9 and 12 willcontinue together until projection 9 turns to pass under the wheel E,and thus passes out of disengagement with pawl 12, and then the gate Cwill be free to be closed. Meantime the projection 8 is carried the samedistance up on the other side of the chain 6, and now projection 8 is upand projection 9 is down. The 'dog or pawl 14 now becomes a factor inthe case, and when the platform reaches the open landing and the parts 9and 12 are near to disengaging position the dog or pawl 14L has passedprojection 8 and dropped in beneath the same. Now as disengagement ofdog 12 occurs dog 14 is in position to lift on projection and thusprevent too sudden or violent closing of the gate. The reverse of thisoccurs when the elevator is going up. Then dog 12 drops in overprojection9 and prevents sudden closing of the gate. In one case thepawl opens the gate by power. In the other case it prevents the gatefrom too rapid closing by reason of Yitsweight and bearsagainst'thisweight;thu s letting the gate close only as fast as theelevator moves.

Each of the successive landings and gates are provided with theseimproved connections, andvaretindependent of one another. and} havetheir own operation. Thezrope oncableg D is just long enough to pay allout when the gate is down, so that it will always be stretched andwill:not run by. on a backw-ard rotation and get slack. It will also benoticed that only a single set of sprocket-wheels and a singlesprocketrchainiis :neededibythiscon- I struction, and likewise a singlepulley atany one time; but the pulley is an exchangeable. member, andtherefore is mounted by the side of sprocket wh-eel E in 'su chway astoibeieasily 3 quentlythe exact rise is not knowntill the place visreachedito putthe mechanism-and again'the-re 'lnaybedemand for variationon different 'iioors in the-same shaft. "Now inf order that 'all theworknecessary'to adapt thei parts :to' varying elevations may'beantici-v pated and provided for in the factory 1 con struct sprocketwheelsof the same size and chains of -the same "length'for all placesand;

put them up always with the samebrackets inithe same way. The distancebetween projections 8 and 9 and the space between dogs 12 and 14 willtherefore be the same at all times and places, and perfect uniformity asto these parts will be maintained wherever athese .-attachments arefound. Then :toget :more rise olf gatel simply; put on a larger pulley,and each pulley may be marked for size according as it is to travelseven, eight, or nine "feetzin 'three' rotations, or any other distance.The only difierence then is found in the size of the pulley, and suchsize is chosen IOU-11' of*the:assortmentonhandas the *landing reguiresandithat.isall that is required.

What I claim as new, and desire to secure by Letters Patent, is-- Theattachment described, comprising a single pair. of fsprockehwheels anda1 chain, projections on .said chain .and .dogs on :the relevatorplatform:toengagethe-same, the gate :and fits cable, .a pulley for saidcable l and means te-securethe;pul1ey;removably at the side oftheilowensprocket wheel,whereby one rSi-ZG orzanother .of -.cable=pulley;may the :employed,.-substantially.asrdescribed.

Witness ,myhanjd Lto'ihe foregoingspecification .this'119th'1day. ofMarch, .1896.

